That is not an easy question to answer, because it is a controversial subject. I think what has made humans unique is a combination of different properties that have a lot to do with emergent properties. First and foremost is the use of complex language, an ability we do not share with any other species. Second, we are able to read the emotions and mind of others, which has made us a highly cooperative species amongst ourselves. Finally, I would say humans have a great facility for mental time travel, in the sense that we can access the past with a very rich memory and, at the same time, are able to visualize a range of alternative futures depending on our decisions. With regard to this latter aspect, I like to say that humans are storytellers.

Not exactly. We share the ability to have values or understand the needs of other members of our species with other animals. However, humans are a symbolic and complex species with an enormous capacity to put ourselves in the minds of others. The ability to do that quite likely led to an understanding of our own mind, meaning human self-awareness was an accident of evolution.

There is a hypothesis of movement, which I personally consider very compelling, whereby the emergence of organisms with the ability to grasp their environment, and which must move to find food and resources, was a key driver in the evolution of brains. It strikes me as a very valid idea for which the case of plants offers the perfect counterexample, as they do not require any complex cognition to get what they need. A good film that illustrates this is The Day of the Triffids, which is about some plants that are smarter than others because they have to move to find food.

There is a hypothesis of movement, which I personally consider very compelling, whereby the emergence of organisms with the ability to grasp their environment, and which must move to find food and resources, was a key driver in the evolution of brains

Cinema is a very good resource that I have been using for a long time to connect with students, although I connect less and less these days, as everything seems to suggest that today’s students no longer watch much cinema. Some films, such as Blade Runner or Ex Machina, are ideal for asking students the big questions in science or life. Science-fiction films are an undeniably good resource.

In some ways, it is. Many ideas that, until recently, fell into the realm of science fiction have gradually become reality over the years. Sometimes, working with other researchers at the lab in the field of synthetic biology, we will remark that some of the new ideas we jot on the board sound like science fiction, but we say it with the conviction that, within a few years, they will no longer be fiction but reality.

Many ideas that, until recently, fell into the realm of science fiction have gradually become reality over the years. Sometimes, working with other researchers at the lab in the field of synthetic biology, we will remark that some of the new ideas we jot on the board sound like science fiction

It is the eldest child of the genetic engineering of the 1980s and 1990s. It is a discipline that revolves around the idea that we can build circuits, usually based on genetic systems, using any species we have analysed in the past, and assemble all sorts of behaviours and tasks, especially within bacteria, but also within mammalian cells, that these bacteria or cells normally do not do. This offers a range of possibilities, from creating a molecule that nature does not synthesize to manipulating bacteria to behave like ants, so they can solve situations collectively, something that evolutionarily has never happened.

Not yet.

I’ve learnt from experience not to speculate about dates or deadlines.

First, there is basic research that needs to be advanced. One of our main lines of research is precisely to use synthetic biology to interrogate nature and evolution. In other words, why haven’t some of the things we can imagine or even build happened? That will give us clues as to which paths evolution may or may not follow. That said, making microbial or engineered cellular systems engage in collective behaviour opens the doors to many things, such as having your system make complex decisions in the context of a complex disease.

Some days it sure doesn’t seem like it, does it? But the answer is yes, humans do learn from our mistakes because we are the species that can best understand and analyse the past to make the best decisions for the future.

Yes, it’s true. It is a conflict we will need to resolve in the near future. We are a cooperative species that comes from a cooperative past that has modified our environment on a very large scale. Paradoxically, our inability to understand the long term makes it very hard for people to understand that if we do not make collective decisions, we will pay dearly for it in the future.

On the one hand, there is no theoretical or fundamental objection preventing that from happening. So we may come to see an intelligent machine that is self-aware. Paradoxically, it is possible that such a reality could come to pass without our understanding why. Nevertheless, we are still far from reaching such a scenario because, for now, we only have artificial systems that perform hyperspecialized tasks with no connection to their environment. In a certain sense, it is as if they were living in a dark room; there is no mind to think or make decisions, or even understand what it is doing.

Yes, and that gives rise to some interesting paradoxes. As I said earlier, humans have learnt to read each other’s minds. We do this, above all, by recognizing faces, which are the vehicle through which we do this mind reading. By extension, we can read the face of a machine and feel empathy for things that are not alive. In a way, it is similar to what happens with our pets, onto which we project a lot of emotions, sometimes without any basis, but at least pets listen to us, whereas machines do not.

Thirty years ago, the physicist and biologist Francis Crick asserted that consciousness should cease to be a subject of study exclusive to philosophers. In his view, consciousness should become a research subject. It is worth recalling that consciousness is a subjective experience, which makes it absolutely unique in relation to any other type of problem posed by science.

Absolutely. We should not think of science as the only way to approach problems.

No. Religion is not compatible with science, even though some of my colleagues believe otherwise. But religion requires you to believe that the natural world can be cancelled, and that is not possible.

Religion is not compatible with science, even though some of my colleagues believe otherwise. But religion requires you to believe that the natural world can be cancelled, and that is not possible. 

I did, and it is a real tragedy. The most surprising thing is that these same politicians or leaders are constantly talking about climate change or technological progress, yet, with a few exceptions, they have no scientific training. I think it is absolutely necessary for these people to have a scientific background, and, if they do not, they should always seek the counsel of scientists when making decisions, which unfortunately rarely happens.

No doubt it is. I remember, many years ago, when AIDS killed millions of people, people said we had learnt our lesson and that we would be prepared for the next global epidemic. But when COVID came along, it seemed like we had learnt nothing. And we know full well that human pressure on the environment is only growing and, therefore, that contact between humans and species with which we would not otherwise have any contact is growing too. It is thus virtually impossible for another zoonosis not to happen. But I want to be optimistic and believe we will be ready for the next pandemic. The good thing is that we have seen just how much science can do, thanks to the personal sacrifice of many people who have worked day and night to tackle and solve this pandemic.

That is a very serious problem. We always talk about the need for society to have good critical judgment. But, really, to what extent do we teach critical thinking in primary or secondary school? I see it with my students, who are very good. They have not spent long enough under an umbrella that teaches them to question the information we receive. We should not automatically believe what someone says just because they say in on social media.

Yes, but that need not be a problem in itself. By definition, scientists are the first to question everything, including our own work. We then separate what is scientifically correct from what is not. Unfortunately, this questioning of reality is not widespread in society.

It is, and it has all the mathematical properties of one. For example, it can spread very efficiently through complex networks with hyperconnected elements. Just as with pandemics, there are hyperconnected nodes that generate and spread false information, which is actually disinformation, which spreads very quickly.

I repeatedly tell my first-year students that there are three things you should always question. The first is the principle of authority, that is, we should not necessarily believe what someone says just because they are a lecturer or professor. The second is the revelation of a fact or idea, which we should never simply accept as an act of faith. And the third is tradition, in the sense there are many things that have been done a certain way for a long time purely out of tradition, but that does not necessarily mean they are right, such as slavery.

I have two kids, so I need to be optimistic [laughter]. Right now, we are at a crossroads. I am referring to climate change, which everyone is always talking about to the extent that we may even have talked about it too much. But the fact is that we have a time window of twenty or thirty years to make the right decisions. If we don’t, the planet will very quickly reach a level of warming beyond our control, which will spell the end of our civilisation. Can we avoid it? Yes, I think there is still time, but we have to act now.